Positions Held

  • Present 2015

    Commissioner of Health and Human Services

    State Ministry of Health, Kaduna State

  • 2011 2011

    Member

    Science and Technology, : National Policy

  • 2009 2009

    Member

    NIPRID, Interview Panel for Director General Nigerian Institute of Pharmaceutical Research and Development

  • 2009 2009

    Chairman

    Science Sub-Complex-Appointment and Promotion Commission, Ahmadu Bello University, Zaria

  • Other Positions Held

Education & Training

  • Ph.D. XXXX

    Ph.D. in Biochemistry

    Ahmadu Bello University, Zaria

  • M.Sc.XXXX

    Master of Science, Biochemistry

    Ahmadu Bello University, Zaria

  • B.Sc.XXXX

    Bachelor of Science in Biochemistry

    Ahmadu Bello University, Zaria

Honors, Awards and Grants

  • 2005
    Alexander Von Humboldt Fellowship (AvH) Humboldtainer
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    Institute of Biochemistry Universitat Tuebingen Germany . (Visiting Professor)
  • 2003
    Japanese Society for the Promotion of Science (JSPS) Fellowship
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    Institute of Tropical Medicine Nagasaki University Japan (Visiting Professor)
  • 1998
    Japanese Society for the Promotion of Science (JSPS)
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    Fellowship Institute of Tropical Medicine Nagasaki University Japan (Visiting Associate Professor)
  • 1997
    Alexander Von Humboldt Fellowship (AvH) Humboldtainer
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    Biochemisches Instiut Christian Albretch Universitat Kiel, Germany
  • 1993
    UNESCO Fellowship/Sabbatical
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    Tokyo Institute of Technology
  • Aug-Oct 2002
    Alexander Von Humboldt Fellowship (AvH), Humboldtainer Humboldtainer
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    Kekule I nstitut of Organisches Chemie Und Biochemie Universitat Bonn Germany (Visiting Professor)

Research Projects

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    Characterization of a sialidase (neuraminidase) isolated from Clostridium chauvoei (Jakari strain)

    Enzymology

    A sialidase from Clostridium chauvoei (Jakari strain), an indigenous bacterial strain that causes blackleg in Nigerian cattle and other ruminants was isolated and partially purified by chromatography on DEAE cellulose, hydroxyapatite and phenyl agarose columns. The enzyme migrated as a 65-kDa protein after electrophoresis on sodium dodecyl sulphate polyacrylamide gels.

    It was optimally active at pH 4.5 and 40°C with an activation energy (Ea) of 13.40 kJ mol−1. It had Km and Vmax values of 170 µm and 200 µmole h−1 mg−1 respectively with fetuin as substrate. When sialyllactose (Neu5Ac2,3 lactose) was used as substrate the Km and Vmax values were 8 µm and 5 µmoles min−1 mg−1 respectively. The Clostridium chauvoei sialidase cleaved sialic acids from RBC ghosts of sheep, horse, goat, cattle, pig and mice as well as mouse brain cells, albeit at different rates. .

    The enzyme was activated by Ca2+ and Mg2+ and inhibited by the group-specific reagents diethylpyrocarbonate (DEP) and N-ethylmalemide (NEM). The sialidase inhibitors, 2,3 didehydroneuraminic acid (Neu5Ac2,3en) and paranitrophenyl oxamic acid (pNPO) inhibited the enzyme competitively with Ki values of 40 and 30 µm respectively.

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    DNA vaccination against the parasite enzyme gamma-glutamylcysteine synthetase confers protection against Leishmania donovani infection

    Vaccination.

    In this study the potential of using Leishmania donovani gamma-glutamylcysteine synthetase (glutamate-cysteine ligase, γ-GCS) as a rational target for vaccine development was determined. Mice, immunised with plasmid containing the full gene sequence for γ-GCS (pVAXγGCS) or plasmid alone (pVAX control), were challenged with a high dose of L. donovani amastigotes to give a stringent test of the ability of the vaccine to protect against infection.

    Vaccination with pVAXγGCS resulted in the production of specific IgG1 and IgG2a antibodies and resulted in significantly lower liver parasite burdens compared to controls.

    Protection was also associated with a significant increase in cell-mediated immunity, demonstrated as an increase in nitrite production by ConA stimulated splenocytes, an increase in the percentage of splenic CD3+CD4+ cells, and enhanced granuloma maturation, compared to control values.

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    Enhancing comparative rabies DNA vaccine effectiveness through glycoprotein gene modifications

    Vaccination.

    Enhancing DNA vaccine effectiveness remains a challenge, especially if the desired goal is immunization efficacy after a single dose. The glycoprotein gene from the rabies virus Evelyn–Rokitnicki–Abelseth (ERA) strain was modified by mutation at amino acid residue 333 from arginine to glutamine. The modified and original unmodified glycoprotein genes were cloned separately and developed as DNA vaccines for immunization in mice.

    The intramuscular (IM) route using a single dose (100 μg) of a modified DNA vaccine showed virus neutralizing antibody induction by d30, and 80% of the mice survived a challenge in which 100% of unvaccinated controls succumbed. Similar results were obtained using a single dose (10 μg) by the intradermal (ID) route with one-tenth amount of the DNA administered.

    Administration of single dose of DNA vaccine with unmodified G did not result in the production of detectable levels of virus neutralizing antibody by d30. The results of the IM and the ID routes of administration were statistically significant (P < 0.01). Based on these preliminary results, a modified glycoprotein gene from the ERA rabies virus strain may be an ideal candidate for DNA vaccine efficacy enhancement.

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    Ethnomedical Treatment of Poisonous Snakebites: Plant Extract Neutralized Naja nigricollis. Venom

    Snakebite Treatment.

    The neutralizing effects of methanol extracts of Indigofera pulchra. Willd (Papilionaceae), Aristolochia albida. Duch (Aristolochiaceae), Guiera senegalense. J.F.Gmel (Combretaceae), and Sterculia setigera. K. Schum (Sterculiaceae) were investigated to validate traditional claims of usefulness of the plants in management of poisonous snakebites. Extracts of Indigofera pulchra. and Aristolochia albida. gave 33.3% and 44.4% protection to mice treated with minimum lethal dose of venom; some gross pathologic symptoms of envenomation were alleviated

    However, minimal activities were shown by Guiera senegalense. and Sterculia setigera.. Both Indigofera pulchra. and Aristolochia albida. were found to neutralize the anticoagulant, hemolytic, and phospholipase activity of crude venom.

    This study showed that Indigofera pulchra. and Aristolochia albida. are useful in some pathologic effects of Naja nigricollis. Broadley (Elapidae) venom, and this provides some scientific basis for the use of the plants in management of poisonous snakebites.

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    Mechanism of adsorption of mucin to titanium in vitro

    Enzymology

    Mucin is the main salivary protein in the mouth of animals including man. The present study aims at investigating the role of electrostatic interactions in the adsorption of mucin to titanium in vitro. The binding profile of mucin to titanium was analyzed according to an adsorption isotherm.

    Mucin was dissolved and the solution suspended with native, calcium, magnesium, or potassium treated commercially pure Ti powder, at pH 3.0 and 7.4. The amount of unabsorbed protein in the supernatant fluid was measured. The maximum amount of adsorbed mucin was 0.11 mg/1.0 g of Ti. The mucin-Ti association constant was estimated to be 2.91 ml/mg.

    Pretreatment of Ti with calcium, or magnesium alone, or combined resulted in increased adsorption of mucin to Ti. No increase in adsorption was recorded following pretreatment of Ti with potassium. The results indicate the involvement of electrostatic interactions in the absorption of mucin to Ti.

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    Studies on the degradation of wood sawdust by Lentinus squarrosulus (Mont.) Singer

    Enzymology

    Lentinus squarrosulus (Mont.) Singer, a basidiomycete also known as a white rot fungi, was immobilized on sodium alginate and tested for the effectiveness to degrade wood sawdust (WSD). Untreated and 0.1 M HCl-pretreated WSD samples were separately reacted in a micro-carrier bioreactor (mCBR) and the extent of degradation to form protein, glucose and ethanol was investigated.

    Pretreatment enhanced the production of both proteins and ethanol by average value of 72.0% over untreated WSD samples, after hydraulic retention time of 72 h. The maximum production of protein observed was 0.94 mg/ml-reaction volume and that of ethanol was 6.6 mg/ml-reaction volume, whereas glucose concentration fluctuated due to interconversion to ethanol.

    This report shows that L. squarrosulus (Mont.) Singer have the potentials of degrading WSD samples to important chemical compounds that are not hazardous to the environment.

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A bloodstream Trypanosoma congolense sialidase could be involved in anemia during experimental trypanosomiasis

A.J. Nok2, E O Balogun1 ,J B Balogun2, S Yusuf, H M Inuwa2, I S Ndams, P Sheridan2, D K Inaoka, T Shiba2, S Harada2, K Kita2, K A N Esievo2
Conference Papers Journal of Consumer Psychology, Volume 22, Issue 2, April 2012, Pages 191-194

Abstract

The observed inverse relationship between the amount of RBC m-GAL and PCV in trypanosome-infected animals that receive lactose treatment has revealed an interesting phenomenon that may help to provide an insight into the mechanism of anemia amelioration. From the aforementioned , coupled with our previous observation that the serum of this group of animals possessed an increased ability to cleave galactose from an artificial substrate, 4- Methylumbelliferyl galactose (Nok and Balogun, 2003); we can infer that lactose infusion resulted in an increased amount of a secreted galactose hydrolyzing enzyme. Moreover , a separate group reported that Trypanosoma evansi contained beta galactosidase

In vitro trypanocidal effect of methanolic extract of some Nigerian savannah plants

Andrew J. Nok2, SE Atawodi1, T Bulus2, S Ibrahim2, DA Ameh2, M Mamman2, M Galadima2
Journal Paper African Journal of Biotechnology Vol. 9 (2), pp. 317-321, 26 February, 2004

Abstract

Abstract Methanol extracts from twenty three plants harvested from the Savannah vegetation belt of Nigeria were analyzed in vitro for trypanocidal activity against Trypanosoma brucei brucei and Trypanosoma congolense at concentrations of 4 mg/ml, 0.4 mg/ml and 0.04 mg/ml. Extracts of Khaya senegalensis, Piliostigma reticulatum, Securidaca longepedunculata and Terminalia avicennoides were strongly trypanocidal to both organisms while extracts of Anchomanes difformis, Cassytha spp, Lannea kerstingii, ..

Partially purified polygalacturonase from Aspergillus niger (SA6)

Andrew J. Nok2, Mohammed L. Buga1, Sani Ibrahim2
Journal Paper African Journal of Biotechnology Vol. 9 (52), pp. 8944-8954, 21 December, 2010

Abstract

Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger)(SA6), partially purified and characterized. The PG showed two bands on SDS-PAGE suggesting an “endo and exo PG with apparent molecular weights of 35 and 40 KDa, respectively. It was purified 9-fold with a yield of 0.18% and specific activity of 246 µmole/ml/mg. The KM and Vmax of the enzyme were 2.74 mg/ml and 0.78 µmole/min/mg, respectively. The optimum temperature and optimum pH of the enzyme were 40 C and 4.5, respectively. The PG was found to be ...

Partially purified polygalacturonase from Aspergillus niger (SA6)

Andrew J. Nok2, Mohammed L. Buga1, Sani Ibrahim2
Journal Paper African Journal of Biotechnology Vol. 9 (52), pp. 8944-8954, 21 December, 2010

Abstract

Polygalacturonase (PG) was isolated from Aspergillus niger (A. niger)(SA6), partially purified and characterized. The PG showed two bands on SDS-PAGE suggesting an “endo and exo PG with apparent molecular weights of 35 and 40 KDa, respectively. It was purified 9-fold with a yield of 0.18% and specific activity of 246 µmole/ml/mg. The KM and Vmax of the enzyme were 2.74 mg/ml and 0.78 µmole/min/mg, respectively. The optimum temperature and optimum pH of the enzyme were 40 C and 4.5, respectively. The PG was found to be ...

Purification and biochemical characterization of lysosomal acid phosphatases (EC 3.1. 3.2) from blood stream forms, Trypanosoma brucei brucei

Andrew J. Nok1, E Amlabu1, AJ Nok1, AB Sallau1
Journal Paper Journal of Parasitology International, Volume 58, Issue 3, 30 September 2009, Pages 238-242

Abstract

Three Acid phosphatases (ACP) were isolated and characterized from the lysosomes of blood stream forms of Trypanosoma brucei by a combination of isopynic and differential centrifugation through Ficoll, organic solvent precipitation, ion exchange on DEAE cellulose 52 and size exclusion chromatography on Sephadex G-75 columns. The purified ACP emerged as three distinct peaks (ACP I, ACP II and ACP III) with high specific activities and they moved homogenously on 12% SDS-PAGE each as a single band with relative ...

Trypanocidal Activity of an Organotin Compound (Tri-n-Butyltin Oxide) toward Trypanosoma brucei

A. J. Nok1, Andrew J. NOK1, King A.N. ESIEVO2, Adaudi ARMBROSE1, Achoba I. ISAAC1, Gimba C. EMMANUEL4, Musa O. SOLOMON1, Kagbu A. JAMES4
Conference PapersJournal of Clinical Biochemistry and Nutrition Vol. 13 (1992) No. 2 P 81-85

Abstract

The organotin compound Tri-n-butyltin oxide was found to possess trypanocidal activity against Trypanosoma brucei. In vitro studies with the drug at 200μg/ml immobilized and lysed the parasites. In vivo experiments in infected rats at a dosage of 10mg/kg/day for 4 consecutive days completely cleared the blood of the parasites. Pathological analysis of the brains, kidneys, and livers of the treated animals did not reveal any abnormalities 6 weeks post-treatment. However, parasite-altered kidney Na+, K+-ATPase kinetics was observed to be rectified post-treatment.

A Bloodstream Trypanosoma congolense Sialidase Could Be Involved in Anemia during Experimental Trypanosomiasis

Andrew J. Nok1, Emmanuel O Balogun1
Journal Paper Journal of biochemistry Vol. 133 (2003) No.6 P 725-730

Abstract

An aqueous extract of defatted leaves of Azadirachta indica was found to possess trypanocidal activity against Trypanosoma brucei brucei. Column chromatography of the crude extract gave three fractions, I, II, and III, that eluted with ethylacetate/methanol, benzene/methanol, and acetic acid/methanol, respectively. Of these extracts, only fraction III retained trypanocidal properties and cured mice chronically infected with Trypanosoma brucei brucei. Histopathological studies of the brains, livers, hearts, and spleens of the treated mice showed no cellular infiltrations. These findings are discussed in relation to trypanosome chemotherapy.

A Bloodstream Trypanosoma congolense Sialidase Could Be Involved in Anemia during Experimental Trypanosomiasis

Andrew J. Nok1, AU Wurochekke1
Journal Paper African Journal of Biotechnology 3 (9), 481-483

Abstract

The in vitro trypanocidal activity of 13 medicinal plants used by local herdsmen in Northern Nigeria for the treatment of trypanosomosis was investigated. Forty-four different extracts prepared from the 13 plants were screened for in vitro activity against Trypanosoma brucei brucei. Four of the extracts showed activity against the parasite at minimum concentration of 8.3 mg/ml of blood.

Pathogenesis and pathology of blackleg in ruminants: The role of toxins and neuraminidase. A short review

Andrew J. Nok2, N.M. Useh3, K.A.N. Esievoa1
Journal Paper African Journal of Biotechnology (2011) 3 (9), 481-483

Abstract

There is no consensus on the pathogenesis of blackleg infection that occurs in ruminants, but toxins and neuraminidase produced by Clostridium chauvoei are believed to play a significant role in the pathogenesis of the disease. This paper provides an update on the role of toxins and neuraminidase in the pathogenesis and pathology of the disease. The use of neuraminidase inhibitors to manage clinical blackleg infections is therefore an alternative therapeutic protocol that should be thoroughly investigated. It is suggested that in vivo clinical trials should be carried out to determine the mechanism of action and clinical efficacy of neuraminidase inhibitors.

Azaanthraquinone inhibits respiration and in vitro growth of long slender bloodstream forms of Trypanosoma congolense

A. J. Nok1
Book John Wiley & Sons | February 1, 2002 | ISBN-doi: 10 .1002/cbf.948:
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Proven strategies for harnessing the power of social media to drive social change

An ethanolic extract of Mitracarpus scaber was found to possess in vitro and in vivo trypanocidal activity against Trypanosoma congolense. At a dosage of 50 mg kg−1 day−1 in normal saline for 5 days, the extract cured Balbc mice infected with T. congolense without any relapse. The isolated active component benz(g)isoquinoline 5,10 dione (Azaanthraquinone) (AQ) purified from the extract was found to inhibit glucose-dependent cellular respiration and glycerol-3-phosphate-dependent mitochondrial O2 assimilation of the long bloodstream forms of Trypanosoma congolense. On account of the pattern of inhibition, the target could be the mitochondrial electron transport system composed of glyceraldehyde 3-phosphate dehydrogenase (G3PDH).

The azaanthraquinone specifically inhibited the reduced coenzyme Q1-dependent O2 uptake of the mitochondria with respect to ubiquinone. The susceptible site could be due to ubiquinone redox system which links the two enzyme activities. Copyright © 2002 John Wiley & Sons, Ltd.

Trypanocidal Potentials of Azadirachta indica: In Vivo Activity of Leaf Extract against Trypanosoma brucei brucei

Andrew J. Nok1, King A.N. Esievo2, Ishaya Longdet1, Samuel Arowosafe1, Paul C. Onyenekwe3, Casmir E. Gimba4, James A. Kagbu4
Journal Paper Journal of Clinical Biochemistry and Nutrition Vol. 15 (1993) No. 2 P 113-118

Abstract

An aqueous extract of defatted leaves of Azadirachta indica was found to possess trypanocidal activity against Trypanosoma brucei brucei. Column chromatography of the crude extract gave three fractions, I, II, and III, that eluted with ethylacetate/methanol, benzene/methanol, and acetic acid/methanol, respectively. Of these extracts, only fraction III retained trypanocidal properties and cured mice chronically infected with Trypanosoma brucei brucei. Histopathological studies of the brains, livers, hearts, and spleens of the treated mice showed no cellular infiltrations. These findings are discussed in relation to trypanosome chemotherapy.

Production and regulation of lignin degrading enzymes from Lentinus squarrosulus (mont.) Singer and Psathyrella atroumbonata Pegler

Andrew J. NOK1, P. A. Wuyep1, A. U. Khan1
Journal Paper African Journal of Biotechnology (2004) 2 (11), P 444-447

Abstract

Abstract The influence of metal ions on the production and regulation of ligninase and mycelia extension of two type Basidiomycetes (Lentinus squarrosulus and Psathyrella atroumbonata) cultivated on lignocellulose waste was investigated. Mn2+ and Ca2+ ions stimulated growth of both fungi and mycelia extension significantly. Ligninase production increased two to twelve fold under the influence of Mn2+ and Ca2+ ions at concentrations of 20 to 80 mM. Mg2+ and K+ ions did not stimulate growth and extension of fungal mycelia

Biosorption of Cr, Mn, Fe, Ni, Cu and Pb metals from petroleum refinery effluent by calcium alginate immobilized mycelia of Polyporus squamosus

Andrew J. NOK1, P. A. Wuyep1, A. U. Khan1
Journal Paper African Journal of Biotechnology (2004) 2 (11), P 444-447

Abstract

Two samples of wastewater were collected and initial concentrations of heavy metals and other elements in wastewater were determined using X-ray fluorescence spectroscopy. Exponentially growing mycelia of the white rot fungus Polyporus squamosus immobilized on calcium alginate was applied to 500 ml of wastewater samples. Biosorption investigations were conducted in a stirring bioreactor. Results obtained showed significant increments in the quantity of heavy metals sequestered by immobilized live mycelia of P. squamosus as

Lecturing

  • Present 2012

    BTEC853: Recent Advances in Biotechnology:

    Topical issues in Biotechnology (Term paper)

  • Present 2012

    FBTE 709: Principles of Forensic Sciences:

    Introduction to Forensic Sciences (definitions, divisions of forensics), Biological specimens (identification, uses, applications).

Specialisation

  • DATE 1981

    Enzymology

    Enzymes are macromolecular biological catalysts. The study of enzymes is called enzymology.

  • DATE 1981

    Medical Biochemistry

    Medical biochemistry addresses the functioning of normal and diseased organisms from a biochemical point of view.

  • DATE 1981

    Biotechnology

    Biotechnology is the use of living systems and organisms to develop products for a specific purpose.

Office

You can find me at my office located at the Department of Biochemistry , Faculty of Science, Ahmadu Bello University, Zaria.

I am at my office every day between 10:00am until 03:00pm, but you may consider a call to fix an appointment.

Laboratory

My lab is the same as my office. My research takes up a considerable amount of my time.

I am available same as above save otherwise specified.